Biology Commons^™

The Role Of Vegetation Architecture In Determining Spider Community Organization, Cynthia L. Hatley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The relationships between vegetation architecture and spider community attributes were examined in a big sage (Artemisia tridentata) community. Spiders were separated into guilds using similarities of species' hunting behavior. Shrub architecture was experimentally manipulated in the field by either clipping 50% of a shrub's foliage to decrease foliage density or tying together a shrub's branches to increase foliage density.

Temporal patterns of spider species density, diversity (H') and evenness (J') showed midsummer peaks in both 1974 and 1975. Seasonal spider guild trends reflected the temporal prominence of a member species or genus. These temporally abundant species appeared to …

The Combined Effects Of Air Temperature, Wind, And Radiation On The Resting Metabolism Of Avian Raptors, Steven R. Hayes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

American kestrels, Falco sparverius; red-tailed hawks, Buteo jamaicensis; and golden eagles, Aguila chrysaetos, were perched in a wind tunnel and subjected to various combinations of air temperature, wind, and radiation. Oxygen consumption was measured under the various combinations of environmental variables, and multiple regression equations were developed to predict resting metabolism as a function of body mass, air temperature, wind speed, and radiation load. Heat transfer analysis of the bird-thermal environment relationship was conducted to produce a biophysical model describing resting metabolism as a function of feather thermal conductance.

Because of differences in surface area to mass …

The Effect Of Architectural Variation In Habitat On A Spider Community: An Experimental Field Study -- With Special Reference To Resource Partitioning, James Vincent Robinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spider community acceptance of, and segregation by, architectural configuration was investigated for the spiders of Green Canyon in northern Utah. Modular habitat units consisting of 30.48 centimeter (1 foot) cubes of chicken wire supporting internal strands of macrame jute tied in different orthogonal configurations were used. Configurations including all three axes were tested at two strand densities.

The primary null hypothesis tested, that spider species use structures independent of architecture, was rejected in favor of the alternate hypothesis that spider species differentially use structures dependent upon architecture. Of the eight most abundant species, two showed preferences for horizontal substrata and …

A Comparison Of Dewpoint And Psychrometric Mode In Leaf Water Potential Measurements, Gladys Durand-Campero

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leaf water potential of two maize plants (Zea mays L.) two chlorophytum plants (Chlorophytwn capense, Kuntze), a schefflera (Brassaia actinophylla) and one aspen (Populus tremuloides Michx.), were measured under laboratory conditions with aluminum block in situ leaf hygrometers and with stainless steel single junction chamber hygrometer using excised entire leaves. Plants were subjected to a drying cycle. The hygrometers were controlled with a dewpoint microvoltmeter and all readouts were recorded on a chart recorder. A typical reading and control schedule included 20 second cooling before a first psychrometric reading allowing the output to …

Genetic Control Of Spermiogenesis In Drosophila Melanogaster: The Effects Of Abnormal Association Of Centrosome And Nucleus In Mutant Ms(1)6s, Douglas Lee Habliston

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mutant ms(l)6S of Drosophila melanogaster is characterized by a spectrum of abnormalities of spermatid differentiation. Included in these are failure of the basal body to make normal attachment to the nucleus, failure of acrosomes to develop, and lack of a normal pupulation of perinuclear microtubules. There is also a failure of normal chromatin condensation and nuclear elongation. The mitochondria do not form a normaI nebenkern, but nevertheless fuse, elongate, and develop paracrystalline bodies. The number of normal axonemes is markedly reduced as a result of the failure of some centrioles to form basal bodies. All of these aberrations can be …

Consumption, Digestion, And Utilization By Goats Of The Dry Matter And Nitrogen In Diets Containing Oak (Quercus Gambelii) Foliage, Anastasios Stefanos Nastis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Part I
A study of animal performance was made with goats fed, ad libitum ground and pe11eted mixtures of Gambe1 oak and alfalfa. Intake, digestibility, metabolizable nitrogen, and metabolized energy of oak diets were generally lower than those for a control alfalfa diet. However, no significant differences in live weight gains of experimental animals were found. No apparent toxicity was detected in goats fed diets containing up to 80 percent oak for 72 days.

Part II
Mixtures of oak (Quercus gambelii) and alfalfa (Medicago sativa) were used to evaluate three laboratory techniques, the Tilley and Terry …

Density And Diversity Responses Of Summer Bird Populations To The Structure Of Aspen And Spruce-Fir Communities On The Wasatch Plateau, Utah, Janet Lee Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sixteen stands representing a range of structural variation in aspen, mixed aspen-conifer, and spruce-fir communities of the Wasatch Plateau, Utah, were censused by the sample count method. The stands were classified as eleven community types based on the understory dominants or indicator species and the cover types. Fifty bird species were recorded during the two seasons; thirty-two occurred in aspen cover, forty-four in mixed aspen-conifer cover, and twenty-two in spruce-fir.

Comparisons of the composition and density of bird populations were made between uniform stands of a single life form and more structurally complex stands of either single or mixed life …

Autoecology Of The Ruderal Weed Heterotheca Grandiflora With Emphasis On Germination Dimorphism, Stephan Dexter Flint

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Weedy species, as they occupy diverse and unpredictable environments, are expected to possess considerable variability in numerous characteristics, including germination. The visually dimorphic achenes of Heterotheca grandiflora Nutt. (Asteraceae) were tested for potentially adaptive differences in their germination, the establishment of the resulting seedlings, and the relative production of the two achene types.

Achenes produced by the disc florets are adapted for dispersal and rapid germination while the ray florets produce smaller achenes lacking a dispersal mechanism, but possessing a more sophisticated physiological system capable of regulating germination. Ray achene germination rates were significantly influenced by different soil surfaces while …

Influence Of Corynebacterium Insidiosum On The Water Relations Of Alfalfa, Rastri Dey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of Corynebacterium insidiosum (McCull) H. L. Jensen on the water relations of its host, alfalfa, was studied by field measurements made on a 6-year-old stand of Ranger alfalfa. Periodic measurements of stomatal conductance, xylem pressure potential Ψ, and root, stem, and leaf conductance were made in relation to soil moisture conditions. Water regain and electrolyte leakage studies were also made to test membrane integrity in diseased plant leaves.

At all times the xylem pressure potential Ψ was found to be much more negative in diseased plants than in healthy plants. Stomatal conductance was found to respond to the …

A Preliminary Investigation Of The Lipid Of Halophilic Bacteria As A Food Additive, Neil F. Collins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to evaluate the feasibility of obtaining workable quantities of the unusual ether-linked phosphatidyl glycerophosphate of halophilic bacteria through batch culture of Halobacterium halobium. Once isolated and purified, physical, emulsification, and toxicological properties of the lipid were evaluated with respect to its use as a nonnutritive lipid substitute or an emulsifier by the food industry. These evaluations included physical descriptions, melting properties, hydrophile-lipophile balance (HLB) determination, and oral and intraperitoneal administration of the lipid to laboratory mice.

Fine Structural Aspects Of The Developing Eye Of The Honey Bee, Judith Susan Eisen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The post-embryonic development of the compound eye of the worker honey bee was investigated with the light and electron microscopes. The cells of the optic primordium were reorganized into preommatidial cell clusters during the late third and early fourth larval instars. Each cluster contained nine prospective retinula cells, the ninth was centrally located and shorter than the other eight; four prospective cone cells; and an undetennined number of prospective pigment cells.

Rhabdomere development began in the eight peripherally located retinula cells just prior to pupation. Following pupation, each ommatidium elongated. During ommatidial elongation, the short ninth retinula cell moved from …

Nitrogen Cycling In A Microcosm Simulation Of The Northern Arm Of The Great Salt Lake, John C. Stube

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen cycling was studied in the hypersaline northern arm of the Great Salt Lake (332,480 mg/l total dissolved solids) using a sediment-water microcosm simulation of that system. The study demonstrated that nitrate, ammonia, and urea were not stimulating to the halophilic bacteria in the microcosm. The bacteria were simulated only indirectly simulated bacterial growth. In addition, no nitrification could be demonstrated during the study.

Weekly analyses of water samples from the north arm of the lake itself showed that nitrate and nitrite were absent, leaving ammonia as the only significant form of inorganic nitrogen in the northern lake basin. Other …

Insect Consumption Of Seeded Rangeland Herbage In A Selected Area Of Diamond Fork Canyon, Utah County, Utah, Diane M. Bowers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study compares insect and cattle consumption of crested wheatgrass (Agropycon spp.) on a site in Sterling Ranch, Utah County, Utah. The hypothesis tested is that insect consumption in general, and specifically consumption by Labops hesperius Uhler, significantly reduces total available cattle forage.

Labops and grasshoppers were probably the major cause of secondary damage at the study site, while the impact of thrips is unknown. A detrimental impact on range was suggested by the data, as insects consumed forage equivalent to 2.8 animal units per month, while cattle consumed forage equivalent to 2.1 animal units per month at the …

Host And Habitat Preferences, Life History, Pathogenicity And Population Regulation In Species Of Protocalliphora Hough (Diptera: Calliphoridae), Terry Lee Whitworth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The host, habitat preferences, and life histories of species of Protocalliphora were investigated in northern Utah. The effect of species of Protocalliphora on blood levels (hematocrit and hemoglobin) and weight gains of nestling birds also was studied.

A total of 1,819 bird nests were examined, representing 68 bird species from 10 habitats. Forty-eight percent (869) of the nests of 51 bird species found were infested. Eighteen species of Protocalliphora, including 11 undescribed, were collected.

Birds experiencing a high rate of infestation included most colonial nesters (such as bank swallows and yellow-headed blackbirds), cavity nesters (such as starlings and tree swallows, …

Ecological Management Of The Alfalfa Leafcutter Bee, Megachile Pacifica (Panzer), With Emphasis On Diapause Induction, Ron M. Bitner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of photoperiod and temperature on diapause induction in the alfalfa leafcutter bee, Megachile pacifica (Panzer) (=M. rotundata Auct.), were studied during the summers of 1972, 1973 and 1974, The influence of photoperiod and temperature on mortality, rate of development and incidence of diapause was measured during the developmental stages of this insect. The aim of this research was to assess the potential for manipulation of the number of generations of this bee per season so as to develop a practical and ecologically-sound method of management,

Eggs, larvae, pupae and adults of M. pacifica were subjected to regimens …

Dispersion Of The Host Specific Phytophagous Insects Of Duncecap Larkspur (Delphinium Occidentale) In The Wasatch Mountains Of Utah, Robert L. Bayn Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Populations of Delphinium occidentale (Ranunculaceae)were monitored over two summers for the presence and dispersion of various life stages of several host specific phytophagous insects. Observations were made at several sites in the Wasatch National Forest east of Logan, Utah. Two species of larkspur aphid (Aphis rociadae and Kakimia wahinkae) were encountered. Although dispersal of alate individuals resulted in widespread infestation of the host plant population, aphids occurred initially on the same one or few plants at each site both springs. Little coexistence of the two species of aphid on the same plant was observed, perhaps because they partitioned …

In Situ Nitrogen Fixation In Cold Desert Soil-Algae Crust In Northern Utah, Darwin Levoy Sorensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen fixation, as measured by the acetylene-ethylene assay, in the surface soils of southern Curlew Valley, Utah-Idaho was studied. The removal of nitrogen from the surface soil by precipitation runoff water was also studied, and the role of the soil-algae crust in preventing erosive loss of nitrogen was evaluated.

Nitrogen fixation during the study year was estimated to be less than 10 kg/ha. This level is probably sufficient to maintain steady-state on an annual basis in standing crop nitrogen in this environment.

Well structured, lichenous crusts had improved infiltration of precipitation and lowered erosive loss of nitrogen. Poorly structured and …

Structure Of Songs And Organization Of Singing In Fox Sparrows Breeding In Northern Utah And Southern Idaho, Dennis John Martin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Structure of songs and organization of singing in 133 Fox Sparrows Passerella iliaca were studied during 2 breeding seasons in 3 geographically separate populations in northern Utah and southern Idaho. The structure of songs was analyzed with the aid of an audiospectrograph. The organization of the singing of songs in 56 birds was analyzed by applying Markov chain analyses to the sequences of songs uttered.

Songs were composed of syllable-types, of which 49 were recognized. Syllable-types could occur singly or be serially repeated within songs, but they were never fractured so that only a portion of one would be in …

Regulation Of Rabbit Testicular Capsular Motility: The Interaction Of Prostaglandins, Acetylcholine And Sympathomimetic Agents, James L. Hargrove

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The regulation of the contractility and intratesticular pressure of rabbit testes was studied. The effects of, and interactions among, prostaglandins (PGs) E₁ and F_2α testosterone, acetylcholine, epinephrine and norepinephrine were ascertained both in vitro and in vivo. All of these compounds, except for high concentrations of PGE₁ and testosterone, stimulated the testicular capsule to contract. PGE₁ at low concentrations potentiated the contractions produced by epinephrine and acetylcholine. Above 10^-7M, PGE₁ inhibited contractions caused by PGF_2α epinephrine or acetylcholine. Testosterone inhibited contractions caused by PGF_2α in vitro.

Preinjections of rabbits …

Monoamine Oxidase As A Target Enzyme In Pineal And Testicular Tissue: Adrenal Cortical Steroids And Arginine Vasotocin, Randall James Merrill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of the research was twofold: (a) To ascertain what effects the adrenal glucocorticoids and catecholamines have on pineal N-acetyltransferase and monoamine oxidase activity, and (b) to observe what effect arginine vasotocin (a pineal polypeptide) has on testicular monoamine oxidase activity.

Rat pineal N-acetyltransferase activity was numerically increased when rats were injected with cortisol. It was increased significantly when the animals were injected with cortisol plus norepinephrine. Adrenal demedullation significantly increased N-acetyltransferase activity in starved rats when compared with intact control animals. Moreover, bovine pineal monoamine oxidase activity was markedly inhibited in a dose-dependent manner when incubated in vitro …

Respiratory Metabolism And Energy Requirements Of Embryo, Larval And Juvenile Mountain Whitefish, Prosopium Williamsoni, Pokkavil Karunakara Rajagopal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The upper optimum temperature for embryonic development of mountain whitefish is 6 C, and for the post yolk sac stage is 9 to 12 C. The need to know effects on all stages in the life cycle in cases of thermal pollution is demonstrated. Abnormalities caused by thermal pollution in hatched larvae were agape jaws, coloboma or fissure of the eye, monophthalmia or the presence of only one eye, monomicrophthalmia or the presence of one small eye and one case of twinning. High mortalities of eggs occurred at 9 C and higher.

Study of the energy expenditure, by the dry …

Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although water stress is an important selective force in many environments, it is not commonly considered to be of particular importance in tundra areas. Even though large portions of tundra may have an abundance of water, other more exposed areas may become quite dry. This microsite variability with respect to moisture stress was reflected in soil water potential measurements obtained from an alpine tundra area on Niwot Ridge in Colorado. Even though soil water potentials were consistently above -5 bars in a relatively low lying Deschampsia meadow, soil water potentials from an exposed fellfield area were often as low as …

Characterization Of Selected Bacteria From The North Arm Of The Great Salt Lake, John L. Crane Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Thirteen bacterial cultures were isolated from the North arm of Great Salt Lake during the months of January and February of 1973. Eleven isolates were gram-negative pleomorphic rods which lysed in hypotonic solution. The remaining two were gram-positive cocci. All isolates and one known strain of Halobacterium salinarium were subjected to examination of morphological, cultural, physiological, and biochemical characteristics. A numerical taxonomic analysis was applied to the compiled characters to compute a coefficient of similarity for each individual isolate as compared to all other isolates. A comparative analysis was included in the similarity computation using characters assembled from those reported …

Life History And Habitat Utilization Of Merriam's Turkey In Southwestern Utah, Fred C. Bryant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study of the Merriam's wild turkey was conducted March 1972 to August 1973 in southwestern Utah to determine the life history and habitat utilization. Using transects, bio-telemetry, and observational techniques, information on flocking, hen:poult and sex ratios, and approximate dates for spring dispersal, nesting, and hatching was obtained. Turkey observations in relation to habitat variables were used to determine habitat utilization.

Except during the spring mating season, male flocks remained apart from other turkeys. Hen flocks in fall and winter consisted of adult hens and juveniles of both sexes. Males dispersed from winter flocks in March, and those that …

Influence Of Soil Water Potential And Environment On The Internal Water Status Of Grasses, Ray W. Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The water relations of two grass species, smooth brome (Bromus inermis Leyss.) and intermediate wheatgrass (Agropyron intermedium (Host) Beauv.), were studied under a range of environmental conditions in a growth chamber. The environmental conditions included three temperature regimes (day/night temperatures of 15/10, 20/15, and 25/20 degrees centigrade), and three vapor pressure deficits within each temperature regime (6.2, 8.8, and 11.4 millimeters of mercury). Short wave radiation was maintained at 0.5 calories per square centimeter per minute with a 14 hour photoperiod, and wind speed was constant at 45 centimeters per second.

Six plants of each species were studied …

Meiotic And Mitotic Chromosomes Of Fritillaria Atropurpurea Nutt., John Keith Archibald

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this paper is to provide information concerning the number, structure, and behavior of chromosomes in the plant species Fritillaria atropurpurea. The material used for this investigation included both floral buds and root-tips from actively growing naturally occurring plants collected from populations in both Utah and Nevada, and root-tips from seed germinated in the greenhouse. The results obtained include a karyotype analysis of mitotic chromosomes, a discussion of meiosis, a discussion of B-chromosomes, and a series of photographs depicting the stages of mitosis and meiosis in this species.

Fritillaria atropurpurea has a diploid chromosome number of 24, …

Cytogenetic Effects Of Vitavax Fungicide On Secale Cereale On Allium Cepa, Jack Ernest Staub

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of Vitavax fungicide (2,3-dihydro-5-carboxanilido-6-methyl-1,4-oxathiin) on meiotic chromosomes of rye (Secale cereale) and mitotic chromosomes of onion (Allium cepa) and rye were observed.

The principal aberrations recorded in pollen mother cells of rye were: 1-4 univalents at metaphase I; sticky bridges at telophase I; and micronuclei and misshapen nuclei at the quartet stage.

The principal aberrations recorded in root tip mitoses in onion and rye were: chromosome fragmentation, disintegration, clumping, aggregation and inhibition of mitosis.

All meiotic phases were significantly affected by 1,000, 5,000,10,000, 33,300, 66,600 ppm Vitavax at the 48, 72, and 96 hour …

Regulation Of Rabbit Testicular Capsular Motility: Prostaglandins, Sex Steroids, And Sympathomimetic Agents, Rod R. Seeley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Smooth-muscle active compounds were extracted from rat and rabbit testicular homogenates, and from bathing media of rabbit testicular capsular preparations and were tentatively characterized as prostaglandins. The endogenous prostaglandins were responsible for spontaneous testicular capsular contractions in vitro, but were not solely responsible for spontaneous testicular capsular motility in vivo. In this respect, significantly greater concentrations of prostaglandins were extracted from bathing media from spontaneously contracting capsules in vitro than from inactive capsules in vitro or spontaneously contracting capsules in vivo. No significant difference was observed in the amount of prostaglandin extracted from the bathing media of …

Control Of Rat Testicular Monoamine Oxidase Activity: Age, Seasonality, Melatonin, Hcg, Fsh, Starvation And Irradiation, Ronald Lee Urry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A number of investigations were undertaken to determine what factors control testicular MAO activity. Activity was high in neonatal rats (19 g - body weight), showed a reduced activity at 53 g, was increased at 145-235 g and showed a progressively reduced activity at 415 g, 482 g and 650 g. Hypophysectomy of immature male rats at 3 weeks of age, or mature rats at 10 weeks of age, significantly reduced testicular weight and total MAO activity as calculated on a per animal basis. The specific activity of the enzyme, as expressed on a per mg of tissue basis, was …

Temperature Effect On Leaf Water Potential Measurements, Rex J. Prosser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Silver foil psychrometers were used to monitor water potential in different portions of maize leaves which were subjected to temperature gradients. The psychrometers were preliminarily calibrated over standard NaCI solutions at temperatures ranging from 5°C to 45°C in an aluminum plate apparatus designed to provide uniform temperatures within each psychrometer even while overall temperature was changing. Based on the calibrations, empirical temperature correction equations were derived and used to correct psychrometer readings at different temperatures to equivalent values at 25°C. Temperatures on a single maize leaf were varied by placing the long leaf through an insulated box with several compartments …